L4D2: retail vs mass order vs pre-order

GameSync.net understands that a current Left 4 Dead 2 mass order forum thread on GameAxis promises a cheaper L4D2 price than the retail version. The recommended retail price for Left 4 Dead 2 will be SG$62.

The current Steam pre-order 4-pack for L4D2 is still available. So which of these three options should you go for? GameSync has done a quick comparison of the retail, mass order, and pre-order versions:

Mass order version:

Cheaper than retail version (GameSync understands that the final mass order price might be around $50)